Method of and means for securing damping magnets together



Dec, 1', '1931. F. P. LAUFF ER METHOD OF AND MEANS FOR SECURING DAMPING MAGNETSTOGETHER Filed June 13, 1929 INVENTOR fr'an/(P l aufler.

ATTORNEY Patented Dec. 1, 1931 UNITED STATES PATENT oFFI FRANK P.LAUFIFER, or IRWI PENNSY VANIA, ASSIGNOR ro WESTINGHOUSE 'rnxc & MANUFACTURING COMPANY, conPoRArIoN OF PENNSYLVANIA I I METHOD OF AND MEANS FOR SEC RING-I AMPINGMAGNETS TOGETHER Applieation filed June 13,

My invention relates to damping-magnet structures for integrating meters and relays and more particularly to. methodsof, and means, for securing magnets together.

My invention has for an object to'provide a method of, and means for, securing a pair: of damping magnets whereby they aresubstantially fixed with respect to each other.

Another object of my invention is to prom vide means for securing a pair of magnets with respect to each other without setting up stresses in the magnet structure. 7

A further object of my invention is to provide means for reducing the cost and increas- 1 ing theefficiency of unitary magnet structures embodying a plurality" of permanent magnets. p

My invention is illustrated in the accompanying drawings to which reference is to be t-io made in connection with the following description.

In the drawings: Figure 1 is a view,'in perspective, of a damping-magnet assembly constructed in acll.) cordance with my invention and Fig. 2 is a cross-sectional view of the magnet structure, taken on the line 11-11 of Fig. 1.

Two members 2 and 3 of substantially" I fact that, heretofore, the bracket 4 wasgfifi 2s.) closedC-shape are secured with respect to each other by a bracket 4. The members 2 and 3 are of a magnetizable material which, when subjezted to a magnetic flux, becomes permanently magnetized. The bracket 4 is 5 preferably of a light-weight, easily melted,

non-magnetic metal, such as aluminum.

Themembers 2 and 3 are placed in a retaining mold and clamped in the position they are to occupy with respect to each other.

Melted aluminum is then poured into the mold and, very shortly after it has solidified,

it is cooled by being dipped in water. The temperature of the molten metal is such that the characteristics of the magneticmembers 2 and 3 are not injuriously affected, that is, the temperature is below the critical temper ature of the material of the members 2 and 3 The cooling operation is resorted to in order to prevent the heat of the molded bracket from permeating the members 2 and 3, and to obviate any possibility of the magnetic ,Ina-

1929. Serial No. 370,513.

terial becoming annealed. p As'shown in the drawings, the bracket 4-is V molded around the upper ends of the'mem- ,bersl2 and 3 to hold these members in fixed;

, position with respect to each other. 'Anair "space '5horizontally separates the ends of the members 2 and 3 and an air space 6 separates themvertically. The airspace 6 is provided for the reception of a conducting disc (not; shown), the .movement of which is tov be damped by the flux between the ends of the members 2 and 3. The disc may be aportion of a'relayoran integrating meter, such as a watthour meter, as is well understood bye those familiar with the art. N i

The bracket 4 is secured to the structure of the meter, in the well-known manner, by

A bolts cooperating with openings 7' and Sin the 7 I extensions'9 and 10 provided at one endfof the 5550 bracket in the molding operation.

. It will be apparent that the bracket 4 may be, and preferablyis, provided with the usual full-load adjusting shunts, as well as with temperature-compensating shunts, of which ji the material of the bracket itself may be a part. i c j i The most desirable advance-made by my invention over the prior art resides in the pressed with great pressure by a powerful machine'upon and around theends of the members 2 and3, thereby setting up physical stresses in the material of these members, which stresses weakened the permanent-i magnetic properties thereof, whereas the bracket 4, when moldedaround the ends of members 2 and 3, in accordance with my invention, is subjected only to stresses resulting from the cooling of the material, the latter stresses are much less severe and more uniform than the former.

My device, in addition to securing the magnets together fixedly, may also be manufactured at a reduced cost, when compared Wltllqgi prior structures. i

, After the members 2 and 3 are secured into a unitary structure by the molded bracket 4, they may be magnetized in such manner that adjacent poles are of opposite polarity, aseg indicated by the letters N and S in the drawings. This arrangement has been found to be the most desirable to maintain the magnetic properties of the damping system constant.

I have described the principle of operation of my inventi0n,"tog,ether With the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatusshown and described is only illustrative and that the inventionmaybe exemplified by other specific means.

I claim as my invention:

1. In combination, in .an electrical instrument'unit, a. pairiof strap-like permanent magnets of substantiallyuniform Width and thicknesstthroughout and bent to substan- 20 tiiillylCshape, said "magnets having poleend p'ortions'disposed in spaced quadrature relation andthe pole ends'of each magnet beingfor disposition at the respective sides er an armature disk, and a homogeneous non- .magnetlc metal body molded to the magnets 'andha-v n'g a section of'substantially doubleloop-shap'efor disposition entirely at one side of thedislg'the loopsof said body being disposed about the respective magnets spaced from the adjacent ends thereof, said body having portions between the magnets for attaching the unit to a support and mounting a shunt forcooperation with the magnets.

2.. In combination, inan electrical instru 'ment-unit, a pairof permanent magnets of substantially C-shape, said 1 magnets having pole-end portlons'disposed in spaced quadrature relation andthe pole ends of each magnet being for disposition at' the respective sides of an armaturedisk, and a homogeneous non-magnetic body molded in holding relation to'the magnets having portions between the magnets for attaching the unit to a support and mounting a shunt for 'co-operation with themagnets. In testimony whereof, I have hereunto subscribed my name this 7th day of June 1929. FRANK P. LAUF F ER. 

